Robust enrollment of 173 patients across dose escalation and expansion cohorts, with objective responses observed across five tumor types
JK06 continued to demonstrate a highly differentiated MMAE safety profile with predominantly low-grade, manageable treatment-related adverse events (TRAEs) at doses selected for expansion cohorts
Objective response rate (ORR) of 50% (5 of 10) among response-evaluable squamous non-small cell lung cancer (NSCLC) patients treated at the 4.5 mg/kg dose; overall disease control rate (DCR) of 94% (16 of 17) across all response-evaluable squamous NSCLC patients
Durable anti-tumor activity also observed in non-squamous and EGFR-mutant NSCLC, multiple breast cancer subtypes, and additional 5T4-expressing solid tumors
GAITHERSBURG, Md.–(BUSINESS WIRE)–Salubris Biotherapeutics, Inc. (SalubrisBio), a clinical-stage biotechnology company dedicated to discovering and developing novel complex biologic therapeutics, today announced updated data from the Phase 1/2 study of JK06, a 5T4-targeted antibody drug conjugate (ADC), in patients with unresectable locally advanced or metastatic solid tumors, including non-small cell lung cancer (NSCLC) and breast cancer. The data are being presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting, taking place May 29 – June 2, 2026, in Chicago, Illinois.
“We are proud to have treated 173 patients across our Phase 1/2 study. These updated results are a meaningful step forward for JK06, with particularly compelling efficacy observed in squamous NSCLC, an area of significant unmet medical need. Among response-evaluable squamous NSCLC patients treated at 4.5 mg/kg, JK06 demonstrated a 50% ORR, and overall, we observed a 35% ORR and 94% DCR for 17 response-evaluable squamous NSCLC patients enrolled to date,” said Sam Murphy, Chief Executive Officer of Salubris Biotherapeutics. “These results, together with a consistently favorable safety profile and durable activity across multiple subtypes of NSCLC and breast cancer, reinforce 4.5 mg/kg as a promising dose for continued evaluation and support our plans to advance JK06 into additional monotherapy expansions and as a potential combination therapy.”
The ongoing Phase 1/2, open-label study (NCT06667960) includes dose escalation (1.5 to 8.0 mg/kg) and multiple tumor-specific expansion cohorts in NSCLC, breast cancer, and a basket of other 5T4-expressing tumors. JK06 is administered intravenously once every three weeks (Q3W), with responses assessed per RECIST 1.1. As of May 12, 2026, 173 patients have been treated with JK06, including 42 patients in dose escalation and 131 patients in expansion cohorts. Of the 131 patients treated in the cohort expansion, 64 were NSCLC patients, 44 were breast cancer patients, and 23 were enrolled in the basket cohort.
Key Efficacy Findings:
NSCLC
- Across all response-evaluable squamous NSCLC patients, JK06 achieved a confirmed ORR of 35% (6 of 17), including 50% (5 of 10) at 4.5 mg/kg, and a DCR of 94% (16 of 17).
- Across all response-evaluable EGFR-mutant NSCLC patients, JK06 achieved a confirmed ORR of 43% (3 of 7) and a DCR of 86% (6 of 7).
Breast Cancer
- Across all response-evaluable hormone receptor-positive (HR+) breast cancer patients, JK06 achieved a confirmed ORR of 30% (3 of 10) and a DCR of 60% (6 of 10).
- Across all response-evaluable triple-negative breast cancer (TNBC) patients, JK06 achieved a confirmed ORR of 25% (4 of 16) and a DCR of 69% (11 of 16).
- Six of seven breast cancer responders had received prior ADC therapy, including two with multiple prior ADCs.
Other Tumor Types
- One confirmed partial response was observed among two response-evaluable endometrial cancer patients, representing the fifth tumor type to demonstrate a response with JK06 following NSCLC, breast, gastric and cervical cancers.
Key Safety Findings in Expansion Cohorts (n=131):
- JK06 at doses ≤ 5.2 mg/kg was generally well-tolerated, with TRAEs that were predominantly low grade and manageable.
- The most frequently observed TRAEs (≥ 5% overall) were alopecia (15%), asthenia (15%), dry eye (10%), fatigue (10%), and nausea (10%).
- No Grade 4 or Grade 5 TRAEs were reported.
- Grade 3 TRAEs were uncommon and consisted of keratitis (n=2, 2%), and one case each of fatigue (1%), gait disturbance (1%), and neuralgia (1%).
- Two patients out of 131 (2%) required dose reduction, both due to peripheral neuropathy, and three patients out of 131 (2%) discontinued JK06 (one each due to fatigue, gait disturbance, and pneumonitis).
Details of the ASCO presentation are as follows:
Title: A Phase 1/2 Study of JK06, a 5T4-Targeted Antibody Drug Conjugate (ADC), In Patients with Unresectable Locally Advanced or Metastatic Cancer
Presenter: Omar Saavedra, M.D., New Experimental Therapeutics (NEXT) Oncology, Hospital Universitario Quironsalud, Barcelona, Spain
Abstract #: 552322
Session: Developmental Therapeutics – Molecularly Targeted Agents and Tumor Biology
Date/Time: May 30, 2026 | 1:30 – 4:30 CDT
About JK06
JK06 is a first-in-class quadrivalent, biparatopic ADC that selectively targets 5T4 with a monomethyl auristatin E (MMAE) payload. 5T4 is an oncofetal protein that is overexpressed in a wide range of solid tumors, including non-small cell lung cancer (NSCLC), breast, gastric, and genitourinary cancers, and is associated with more aggressive tumor progression and reduced survival. JK06 has demonstrated picomolar affinity for 5T4 and enhanced internalization resulting from the biparatopic design. Together with stable, site-specific payload conjugation, JK06 has demonstrated the potential for robust efficacy and a favorable safety profile.
About SalubrisBio
SalubrisBio is a clinical-stage biotechnology company dedicated to discovering and developing complex biologics for cardiovascular disease and oncology. The Company is currently progressing multiple innovative and rationally designed first-in-class therapeutics through clinical development programs, including JK07, the potential first disease-modifying biologic for heart failure, and JK06, a quadrivalent, biparatopic ADC targeting 5T4 for the treatment of cancer. SalubrisBio is headquartered in Gaithersburg, Maryland. For more information about SalubrisBio, visit us at www.salubrisbio.com and connect with us on LinkedIn.
Contacts
For further information, please contact:
Argot Partners
212.600.1902 | SalubrisBio@argotpartners.com
